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Clean Air Markets

Analysis of the Final ACE Rule

On June 19, 2019, EPA finalized the Affordable Clean Energy (ACE) rule

Documentation for Analysis of the Final ACE Rule

The EPA's power sector analysis for the final ACE rule uses EPA's Power Sector Modeling Platform v6 using IPM November 2018 Reference Case. Full documentation, including the NEEDS database used for this analysis, is available at EPA’s Power Sector Modeling Platform v6 using IPM website.

IPM Run Files

Download IPM run files for the final ACE rule using the links in the table below. Click on the IPM run name in the first column of the table below to download a file. The files are posted in one of two formats, a zipped archive or an excel spreadsheet, and contain detailed IPM input and output files (i.e., .DAT, System Summary Report, .RPE, and RPT files) for the listed runs. More detailed information on the modeling framework, specific scenarios, assumptions, and other important details of the analysis can be found in the Regulatory Impact Analysis that accompanies the final ACE rule.

  • To facilitate the output visualization of the results, a Results Viewer(19 MB) is available to compare these different scenario projections and link them with historical data.

IPM Run Name IPM Run Description

EPA v6 November 2018 Reference Case (Baseline)(152 MB)

This scenario does not apply any standards of performance under section 111(d) of the CAA for CO2 emissions from existing sources. Furthermore, in this scenario, it is assumed that no source adopts any heat rate improvements.

Illustrative ACE Scenario(152 MB)

This scenario assumes that HRI potential and costs will differ based on unit size and efficiency. Affected sources were divided into twelve groups based on three size categories and four efficiency categories, and the group-specific cost and performance assumptions were then applied to each unit in the group in the illustrative analysis.

CPP (Limited Trading)(166 MB) This scenario includes the Clean Power Plan (CPP) modeled in a similar fashion to previous EPA analytical efforts. More specifically, this scenario utilizes a mass-based implementation of CPP at the state level, with intra-state trading covering existing sources only, and no incremental demand-side energy efficiency investments.
CPP (Regional Trading and Tolling)(165 MB) This scenario represents a mass-based implementation of CPP, assuming a 3-year implementation delay and regional trading using six hypothetical regions.
CPP (National Trading and Tolling)(165 MB) This scenario represents a mass-based implementation of CPP, assuming a 3-year implementation delay and national trading (with the exception of California and RGGI states).
EPA v6 November 2018 Reference Case with 45Q(152 MB) This scenario reflects the baseline plus revisions to section 45Q tax credits for carbon dioxide sequestration stipulated in the Bipartisan Budget Act of 2018.